Date of Award

12-2008

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Legacy Department

Food Technology

Committee Chair/Advisor

Whiteside, William Scott

Committee Member

Darby , Duncan

Committee Member

Cooksey , Kay

Committee Member

Dawson , Paul

Abstract

Alpha-tocopherol and a transition metal, iron, mixture was evaluated as a possible oxygen scavenger. The effects of moisture, amount of transition metal, and thermal processing on oxygen scavenging capability were also investigated. Results showed that alpha-tocopherol and transition metal had 6.72 cc oxygen per gram of oxygen scavenging capacity and 0.11 cc oxygen per gram per day of oxygen scavenging rate.
Nanoencapsulation technology was adopted for the possible oxygen scavenging activation system. Alpha-tocopherol-loaded poly caprolactone (PCL) nanoparticles were prepared by oil in water (O/W) emulsion solvent evaporation with ultrasonification. The effects of PCL concentration, solvent in oil phase, and ultrasonification time on encapsulation efficiency (%), particle mean size, and loading (%) were investigated. Overall, 5% PCL in methylene chloride (DCM) as the solvent in the oil phase coupled with 3 minute ultrasonication time showed the best encapsulation formulation. Therefore, this formulation was selected for further research.
Alpha-tocopherol-loaded nanoparticles and a transition metal in scavenger mixture were evaluated as a heat activated oxygen scavenger. The effects of moisture, amount of transition metal, and thermal processing on oxygen scavenging capability were also studied. Results showed that alpha-tocopherol-loaded nanoparticle and transition metal had 6.44 cc oxygen per gram of oxygen scavenging capacity and 0.21 cc oxygen per gram per day of oxygen scavenging rate. Heat was used as the activator to initiate the oxygen scavenging reaction. However, adding moisture lowered the oxygen scavenging capability.
An active fish gelatin film was developed by customized film applicator and its physical properties and oxygen scavenging capabilities were investigated. The effects of moisture and thermal processing on oxygen scavenging capability were also studied. Alpha-tocopherol-loaded nanoparticles and a transition metal was added into the warm water fish gelatin and cast into a film. Agglomeration of the oxygen scavenger caused a rough film surface, decreased tensile strength, increased elongation at break, and increased oxygen permeability. The active fish gelatin film had an oxygen scavenging capacity of 1969.08 cc oxygen per square meter per mil thickness with water as the activator which triggered the oxygen scavenging reaction. However, thermal processing at temperature above 140oF destroyed the oxygen scavenging ability of the film.

Included in

Engineering Commons

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